Alkaline batteries are currently widely used as main power sources for toys as everyday items, game machines, mobile electronic equipment, and other devices, and are thus desired to have long lifetime when being used in such devices. To achieve a long driving time of a device, it is necessary to fill a battery with a large amount of an active material, which requires an increase in content of manganese dioxide serving as a positive electrode active material.
Patent Document 1 describes a technique for increasing the capacity by reducing the ratio of graphite in a conductive agent to be added to the positive electrode and also by using expanded graphite with priority.
Patent Document 2 describes a technique for obtaining a large-capacity battery with reduced expansion of a battery case by employing a thin body for the battery case and defining the filling density of graphite.
Patent Document 3 describes a technique for improving discharge performance under an intermediate load by controlling the half-width of a 110 plane of the crystal structure of manganese dioxide and the potential thereof. Patent Document 4 describes a technique for improving discharge performance under a high load and a low load by adjusting the ratio of the 110 plane to a 021 plane within a predetermined range.